Waveguide switches are used in microwave systems to connect or disconnect one or more waveguide sections to other waveguide sections. These switches can be either manually or electromechanically operated.
Generally where two or more waveguide switches are required in a system, discrete switches are cascaded, as seen in FIG. 1, where four DPDT transfer waveguide switches 10a, 10b, 10c and 10d having discrete stator housings 1, 2, 3, and 4 are interconnected, in series by interposed flanges 11 and waveguide sections 12. This arrangement results in lowering of such RF parameters as VSWR and insertion power. In the electromechanically operated multiple switch waveguide, each switch is driven by a switch motor or actuator. An example of one such motor or actuator can be seen in U.S. Pat. No. 4,795,929. These motors are usually two position devices and have stringent duty cycle requirements. If the duty cycle is exceeded the motors overheat and can burn up. Implementing duty cycle protection in software for computer controlled systems is one means of protection, albeit one that can be overridden and subject to error. Further, irrespective of how duty cycle protection is implemented, the environment in which any motor control logic circuitry must work is demanding owing to the noise generated by operation of the switch motors and relays. This noise, including large inductive spikes, if not filtered or decoupled from the control logic circuitry will cause erratic operation and possibly failure of such logic.
It is an object of the present invention to provide an arrangement of a multiple array of waveguide switches having a common stator.
It is also an object of the present invention to provide a wave guide assembly in which a plurality of switches are housed in a common or monolithic assembly, thereby avoiding the excessive use of flanges and other connecting members.
It is a further object of the present invention to provide the means for independently driving each switch motor in a multiple array of same.
It is a still further object of the present invention to provide an interface control circuit between a digital computer and each switch motor of a multiple switch, common stator waveguide.
It is further object of the present invention to provide control circuitry to operate a multipole waveguide switch motor wherein the circuitry is hardwired so as not to exceed a defined duty cycle.
It is another object of the present invention to provide hardwired control circuitry for independently driving each switch motor of a multiple switch waveguide wherein the circuitry is immune to switching transients associated with the operation of the motors.
Other objects and features of the present invention will become apparent from the following disclosure.